Surge arresters or comparable devices are known from DE 10 2005 036 265 A1 and DE 197 41 658 A1, for example.
Surge arresters can be used in electrical components to protect sensitive component circuits from voltage or current surges—e.g. of a nearby lightning stroke—or other unwanted discharges.
Stacked gas-filled surge arresters usually comprise arrester units being filled with gases e.g. such as noble gases. When a voltage is applied to such an arrester unit that exceeds a specific spark-over voltage, then the resistivity of the arrester unit decreases and the arrester unit becomes conducting. In other words, the arrester unit is activated. When the voltage applied to the arrester unit falls below a specific arc voltage, then the resistivity again increases and the arrester unit becomes isolating again, i.e. the arrester unit is deactivated.
Surge arresters usually connect sensitive circuits to ground. However, if the voltage level of the sensitive circuit relative to the ground potential after activating the arrester unit exceeds the arc voltage of the arrester unit, then the resistivity of the arrester unit cannot increase and the arrester unit stays in its conducting state. Thus, arrester units can be stacked—i.e. cascaded in a series configuration—to increase the possible operating voltage of the sensitive circuit.